The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 03, 1987
Filed:
Jun. 05, 1985
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
148188 ; 148187 ; 2957 / ; 29578 ; 29591 ;
Abstract
After an end part of a polycrystalline silicon film has been oxidized from an exposed side surface thereof, a silicon dioxide film formed is removed, and an opening thus provided is used for diffusing an impurity into a semiconductor substrate so as to form a graft base region. This measure is effective for fabricating a semiconductor device of small required area at high precision.